Battery protection circuit and electronic equipment

Abstract

The utility model provides a battery protection circuit and electronic equipment, the battery protection circuit comprises a first detection module, a second detection module and a protection switch module, the protection switch module comprises a first connection end, a second connection end and a control end, and the first connection end of the protection switch module is used for being connected with a battery pack; the first connection end of the protection switch module is used for being connected with a power source, the second connection end of the protection switch module is used for being connected with a power source, the output end of the first detection module is connected with the control end of the protection switch module, and the second connection end of the second detection module is connected to a node between the first detection module and the protection switch module. When any one of the first detection module and the second detection module breaks down, the battery protection circuit can still provide battery overvoltage charging protection, and the safety of the battery protection circuit is effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery protection, and in particular to a battery protection circuit and electronic equipment. Background Art

[0002] Currently, battery protection on the market usually uses fuses to protect the battery. However, when a fuse is used to protect the battery, the fuse will no longer have a protective function after it blows, and the fuse needs to be replaced. The fuse in the existing solution cannot be reused, which increases the circuit cost. Utility Model Content

[0003] The present application provides a battery protection circuit and an electronic device to solve the technical problem in the existing battery protection technology that fuses cannot be reused, resulting in increased circuit costs.

[0004] In a first aspect, the present application provides a battery protection circuit, the battery protection circuit comprising

[0005] A first detection module, a second detection module and a protection switch module;

[0006] The protection switch module comprises a first connection end, a second connection end and a control end, the first connection end of the protection switch module is used to connect to the battery pack, and the second connection end of the protection switch module is used to connect to the power supply;

[0007] The input end of the first detection module is used to receive a voltage signal from any battery cell of the battery pack, the output end of the first detection module is connected to the control end of the protection switch module, the first detection module is preset with a first voltage, the first detection module compares the voltage signal with the first voltage, and outputs a first control signal to the control end of the protection switch module based on the comparison result, and the protection switch module cuts off the path between the first connection end and the second connection end based on the first control signal;

[0008] The second detection module has a first connection end, a second connection end and a third connection end. The first connection end of the second detection module is used to receive a voltage signal from any battery cell of the battery pack; the second connection end of the second detection module is connected to a node between the first detection module and the protection switch module, and the third connection end of the second detection module is used to connect to a power supply. The second detection module is preset with a second voltage. The second detection module compares the voltage signal with the second voltage, and based on the comparison result, conducts the second connection end of the second detection module and the third connection end of the second detection module.

[0009] In some embodiments, the protection switch module is a field effect transistor.

[0010] In some embodiments, the second detection module includes a switch unit and a detection unit, the switch unit has a first end, a second end and a third end, and the detection unit has a first end and a second end;

[0011] The first end of the switch unit serves as the second connection end of the second detection module, the second end of the switch unit serves as the third connection end of the second detection module, the third end of the switch unit is connected to the first end of the detection unit, and the second end of the detection unit serves as the first connection end of the second detection module.

[0012] In some embodiments, the switch unit is a field effect transistor or a bipolar junction transistor.

[0013] In some embodiments, the first detection module is also preset with a first warning voltage, the first detection module compares the voltage signal with the first warning voltage, and outputs a second control signal to the control end based on the comparison result, and the protection switch module turns on the first connection end and the second connection end based on the second control signal.

[0014] In some embodiments, the second detection module is preset with a second warning voltage, the second detection module compares the voltage signal with the second warning voltage, and based on the comparison result, cuts off the path between the second connection terminal of the second detection module and the third connection terminal of the second detection module.

[0015] In some implementations, the second voltage has a value greater than the first voltage.

[0016] In some embodiments, the first detection module also includes a third connection terminal, and the third connection terminal of the first detection module is connected to the positive electrode of the power supply for monitoring the voltage signal of the positive electrode of the power supply. The first detection module is also preset with a third voltage. The first detection module compares the voltage signal of the positive electrode of the power supply with the third voltage, and outputs a third control signal to the control terminal based on the comparison result. The protection switch module cuts off the path between the first connection terminal and the second connection terminal based on the third control signal.

[0017] In some embodiments, the first detection module further includes a voltage stabilizing unit, the voltage stabilizing unit includes a voltage stabilizing resistor, and two ends of the voltage stabilizing resistor are respectively connected between the output end of the first detection module and the node.

[0018] In some embodiments, the second detection module further includes a current limiting unit, the current limiting unit includes a current limiting resistor, one end of the current limiting resistor is connected to the first end connected to the switch unit, and the other end of the current limiting resistor serves as the first connection end of the second detection module.

[0019] A second aspect provides an electronic device, comprising the battery protection circuit of any one of the first aspects.

[0020] The present application can achieve the following beneficial effects: The present application proposes a battery protection circuit and an electronic device. By setting a first detection module and a second detection module, when any one of the first detection module and the second detection module fails, the battery protection circuit can still provide battery overvoltage charging protection, effectively improving the safety of the battery protection circuit. Specifically, when the first detection module is normal and the second detection module fails, the first detection module can output a first control signal to the control end of the protection switch module, so that the first connection end and the second connection end of the protection switch module are in an off state, thereby protecting the battery pack. When the first detection module fails and the second detection module is normal, the second connection end and the third connection end of the second detection module are turned on, thereby lowering the potential of the control end of the protection switch module, so that the first connection end and the second connection end of the protection switch module are in an off state.

[0021] Furthermore, when both the first detection module and the second detection module can work normally, the first detection module and the second detection module can be used to simultaneously pull down the potential of the control end of the protection switch module.

[0022] Furthermore, the first detection module and the second detection module may also turn on the first connection terminal and the second connection terminal of the protection switch module when detecting that the voltage signal of any cell of the battery pack is low, so as to restart charging of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0024] Figure 1 A schematic diagram of the structure of a battery protection circuit provided in an embodiment of the present application;

[0025] Figure 2 A schematic diagram of the structure of a battery protection circuit provided in an embodiment of the present application;

[0026] Figure 3 A schematic diagram of the structure of another battery protection circuit provided in an embodiment of the present application;

[0027] Figure 4 A schematic diagram of the structure of another battery protection circuit provided in an embodiment of the present application.

[0028] Reference numerals:

[0029] 20-battery pack; 201-battery cell;

[0030] 30 - first detection module; 40 - second detection module. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0033] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0034] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0035] In the description of the present application, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0036] In the description of this application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0037] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0038] Please refer to Figure 1 In a first aspect of the present application, a battery protection circuit is provided. The battery protection circuit includes a first detection module 30, a second detection module 40 and a protection switch module.

[0039] The protection switch module includes a first connection end, a second connection end and a control end. The first connection end of the protection switch module is used to connect to the battery pack 20, and the second connection end of the protection switch module is used to connect to a power source (eg, P+).

[0040] The input end of the first detection module 30 is used to receive a voltage signal from any battery cell 201 of the battery pack 20. The output end of the first detection module 30 is connected to the control end of the protection switch module. The first detection module 30 is preset with a first voltage. The first detection module 30 compares the voltage signal with the first voltage and outputs a first control signal to the control end of the protection switch module based on the comparison result. The protection switch module cuts off the path between the first connection end and the second connection end based on the first control signal.

[0041] The second detection module 40 has a first connection end, a second connection end and a third connection end. The first connection end of the second detection module 40 is used to receive a voltage signal from any battery cell 201 of the battery pack 20; the second connection end of the second detection module 40 is connected to the node Q between the first detection module 30 and the protection switch module, and the third connection end of the second detection module 40 is used to connect to a power supply (for example, P-). The second detection module 40 is preset with a second voltage. The second detection module 40 compares the voltage signal with the second voltage, and based on the comparison result, the second connection end of the second detection module 40 and the third connection end of the second detection module 40 are turned on.

[0042] For example, in combination Figure 2 As shown, the battery pack 20 can be obtained by connecting a plurality of battery cells 201 in series. Both ends of any battery cell 201 in the battery pack 20 are connected to the first detection module 30, so that the first detection module 30 can detect the battery cell 201 voltage of each battery cell 201. By detecting the voltage of each battery cell 201, overcharge protection can be performed when any battery cell 201 is overcharged, thereby improving the accuracy of protection.

[0043] It should be understood that in the embodiment of the present application, both ends of any battery cell 201 in the battery pack 20 are also connected to the second detection module 40, so that the second detection module 40 can detect the battery cell 201 voltage of each battery cell 201. By performing voltage detection on each battery cell 201, overcharge protection can be performed when any battery cell 201 is overcharged, thereby improving the accuracy of protection.

[0044] As can be seen from the above, in the embodiment of the present application, the battery protection circuit includes a first detection module, a second detection module and a protection switch module, the protection switch module includes a first connection end, a second connection end and a control end, the first connection end of the protection switch module is used to connect to the battery pack, the second connection end of the protection switch module is used to connect to the power supply, the input end of the first detection module and the first connection end of the second detection module are respectively used to receive the voltage signal from any battery cell of the battery pack, wherein the output end of the first detection module is connected to the control end of the protection switch module, and the second connection end of the second detection module is connected to the node between the first detection module and the protection switch module. By setting the first detection module and the second detection module, when any of the first detection module and the second detection module fails, the battery protection circuit can still provide battery overvoltage charging protection, which effectively improves the safety of the battery protection circuit.

[0045] Specifically, when the first detection module 30 is normal and the second detection module 40 fails, the first detection module 30 can output a first control signal to the control end of the protection switch module to make the first connection end and the second connection end of the protection switch module in an off state, thereby protecting the battery pack 20. When the first detection module 30 fails and the second detection module 40 is normal, the second connection end and the third connection end of the second detection module 40 are turned on, thereby lowering the potential of the control end of the protection switch module, so that the first connection end and the second connection end of the protection switch module are in an off state.

[0046] Further, when both the first detection module 30 and the second detection module 40 can work normally, the first detection module 30 and the second detection module 40 can be used to simultaneously pull down the potential of the control terminal of the protection switch module.

[0047] Specifically, when the battery protection circuit of this embodiment is connected to the positive electrode (P+) and the negative electrode (P-) of the charging power source, the complete charging and protection process is as follows:

[0048] When the battery pack 20 is being charged, the first detection module 30 outputs a high level signal to the control end of the protection switch module as a first control signal to open the path between the first connection end and the second connection end of the protection switch module, and the battery pack 20 starts to charge.

[0049] The input end of the first detection module 30 receives a voltage signal from any battery cell 201 of the battery pack 20, and compares the received voltage signal with a preset first voltage. If it is monitored that the voltage signal of any battery cell 201 is greater than the first voltage, it is determined that the voltage signal of at least one battery cell 201 in the battery pack 20 reaches the overcharge protection voltage of the battery pack 20. At this time, the output end of the first detection module 30 will output a low-level signal as a first control signal, so that the first connection end and the second connection end of the protection switch module are in an off state, thereby achieving overcharge protection when any battery cell 201 in the battery pack 20 is overcharged, so as to ensure that the battery pack 20 is not overcharged.

[0050] The first connection end of the second detection module 40 receives a voltage signal from any battery cell 201 of the battery pack 20, and compares the received voltage signal with a preset second voltage. If it is monitored that the voltage signal of any battery cell 201 is greater than the second voltage, it is determined that the voltage signal of at least one battery cell 201 in the battery pack 20 reaches the overcharge protection voltage of the battery pack 20. At this time, the second detection module 40 will turn on the path between its second connection end and the third connection end, so that the potential of the node Q between the first detection module 30 and the protection switch module is quickly pulled down, that is, the potential of the control end of the protection switch module is pulled down, which will also cause the first connection end and the second connection end of the protection switch module to be in the off state.

[0051] It should be noted that the first voltage and the second voltage mentioned above can be set based on the overcharge protection voltage of the battery pack 20, and in some embodiments, the first voltage and the second voltage can be set to be different.

[0052] For example, in some embodiments, the value of the second voltage is set to be greater than the value of the first voltage. Specifically, when the first detection module 30 and the second detection module 40 are both able to work normally, when it is detected that the voltage signal of any battery cell 201 is greater than the first voltage, the first detection module 30 will output a low-level signal to pull down the potential of the node Q, so that the path between the protection switch module and the power supply is cut off. When it is detected that the voltage signal of any battery cell 201 is greater than the second voltage, the first detection module 30 and the second detection module 40 can simultaneously pull down the potential of the node Q, so that the potential of the control end of the protection switch module can be quickly lowered. By setting the second voltage on the basis of the first voltage, the voltage of the battery cell 201 of the battery pack 20 can be judged at multiple levels, multiple protections can be achieved, and the safety of the battery protection circuit is further improved.

[0053] Exemplarily, in the embodiment of the present application, the protection switch module is a field effect transistor. For example, a CFET. The CFET includes an N-type (high level conduction, low level off) transistor, or includes a P-type (low level conduction, high level off) transistor. The CFET has high input impedance, low output impedance, fast switching speed, low power consumption, etc.

[0054] Exemplarily, the first detection module 30 may be a 2nd PTIC.

[0055] Specifically, the first voltage may be 4.5V, the second voltage may be 4.55V, and the third voltage may be 4.6V. The first voltage, the second voltage, and the third voltage may increase in sequence.

[0056] Exemplarily, the second detection module 40 may be a Gauge IC.

[0057] Figure 3 A schematic diagram of the structure of another battery protection circuit provided in an embodiment of the present application.

[0058] The second detection module 40 can also realize the corresponding function in different ways. Specifically but not limiting, for example Figure 3As shown, the second detection module 40 includes a switch unit and a detection unit, the switch unit has a first end, a second end and a third end, and the detection unit has a first end and a second end; the first end of the switch unit serves as the second connection end of the second detection module 40, the second end of the switch unit serves as the third connection end of the second detection module 40, the third end of the switch unit is connected to the first end of the detection unit, and the second end of the detection unit serves as the first connection end of the second detection module 40.

[0059] Exemplarily, in this embodiment, the switch unit is a field effect transistor or a bipolar junction transistor.

[0060] Exemplarily, in this embodiment, the detection unit may be a Gauge IC.

[0061] Furthermore, when the battery pack 20 is in a state of discharge or self-consumption causing the voltage to drop to a certain condition, in order to be able to recharge the battery pack 20 in time, the first detection module 30 is also preset with a first warning voltage. The first detection module 30 compares the voltage signal with the first warning voltage, and outputs a second control signal to the control end based on the comparison result. The protection switch module turns on the first connection end and the second connection end based on the second control signal.

[0062] Specifically, when the battery pack 20 is discharging or self-consuming and causing the voltage to drop to a certain condition, the first detection module 30 outputs a high-level signal as a second control signal to the control end of the protection switch module to turn on the first connection end and the second connection end of the protection switch module.

[0063] Furthermore, the second detection module 40 is preset with a second warning voltage, the second detection module 40 compares the voltage signal with the second warning voltage, and cuts off the path between the second connection terminal of the second detection module 40 and the third connection terminal of the second detection module 40 based on the comparison result.

[0064] Specifically, when the battery pack 20 is in a state of discharge or self-consumption causes the voltage to drop to a certain condition, the second detection module 40 cuts off the path between the second connection terminal and the third connection terminal. The second detection module 40 can work alone to enable the battery pack 20 to start charging again, or it can work together with the first detection module 30 to enable the battery pack 20 to start charging again.

[0065] Furthermore, when the battery pack 20 is in sleep mode, the battery cell 201 of the battery pack 20 generally does not need to be charged. Therefore, in this embodiment, the first detection module 30 also includes a third connection terminal, and the third connection terminal of the first detection module 30 is connected to the positive electrode of the power supply, and is used to monitor the voltage signal of the positive electrode of the power supply. The first detection module 30 is also preset with a third voltage. The first detection module 30 compares the voltage signal of the positive electrode of the power supply with the third voltage, and outputs a third control signal to the control terminal based on the comparison result. The protection switch module shuts off the path between the first connection terminal and the second connection terminal based on the third control signal.

[0066] When the battery pack 20 is in sleep mode, the first detection module 30 can output a low-level signal as a third control signal to the control end of the protection switch module within a preset time by directly obtaining the voltage of the power supply (for example, P+), so that the first connection end and the second connection end of the protection switch module are in an off state, thereby saving power consumption in sleep mode.

[0067] Figure 4 A schematic diagram of the structure of another battery protection circuit provided in an embodiment of the present application.

[0068] Specifically but not limitingly, Figure 4 As shown, the first detection module 30 further includes a voltage stabilizing unit, which includes a voltage stabilizing resistor R1 , and two ends of the voltage stabilizing resistor R1 are respectively connected between the output end of the first detection module 30 and the node.

[0069] The second detection module 40 further includes a current limiting unit, which includes a current limiting resistor R2 , one end of the current limiting resistor R2 is connected to the first end connected to the switch unit, and the other end of the current limiting resistor R2 serves as a first connection end of the second detection module 40 .

[0070] According to a second aspect of the present application, the present application further provides an electronic device, which includes the battery protection circuit of any one of the above embodiments.

[0071] In some embodiments, the electronic device may further include a battery pack 20, and the battery pack 20 is electrically connected to the battery protection circuit. The battery pack 20 includes at least one battery cell 201, such as one battery cell 201 or multiple battery cells 201.

[0072] Specifically, the electronic device may be a device such as consumer electronics and automobiles that require battery power supply.

[0073] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0074] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and that the present application can be implemented in other specific forms without departing from the spirit or basic features of the present application. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive.

Claims

1. A battery protection circuit, characterized in that: The battery protection circuit comprises a first detection module (30), a second detection module (40) and a protection switch module; The protection switch module comprises a first connection end, a second connection end and a control end, the first connection end of the protection switch module being used to connect to a battery pack (20), and the second connection end of the protection switch module being used to connect to a power source; The input end of the first detection module (30) is used to receive a voltage signal from any battery cell (201) of the battery pack (20); the output end of the first detection module (30) is connected to the control end of the protection switch module; the first detection module (30) is preset with a first voltage; the first detection module (30) compares the voltage signal with the first voltage and outputs a first control signal to the control end of the protection switch module based on the comparison result; the protection switch module cuts off the path between the first connection end and the second connection end based on the first control signal; The second detection module (40) has a first connection end, a second connection end and a third connection end. The first connection end of the second detection module (40) is used to receive a voltage signal from any battery cell (201) of the battery pack (20). The second connection end of the second detection module (40) is connected to a node between the first detection module (30) and the protection switch module. The third connection end of the second detection module (40) is used to connect to a power source. The second detection module (40) is preset with a second voltage. The second detection module (40) compares the voltage signal with the second voltage and conducts the second connection end of the second detection module (40) and the third connection end of the second detection module (40) based on the comparison result.

2. The battery protection circuit according to claim 1, characterized in that: The protection switch module is a field effect transistor.

3. The battery protection circuit according to claim 1, characterized in that: The second detection module (40) comprises a switch unit and a detection unit, the switch unit having a first end, a second end and a third end, and the detection unit having a first end and a second end; The first end of the switch unit serves as the second connection end of the second detection module (40), the second end of the switch unit serves as the third connection end of the second detection module (40), the third end of the switch unit is connected to the first end of the detection unit, and the second end of the detection unit serves as the first connection end of the second detection module (40).

4. The battery protection circuit according to claim 3, characterized in that: The switch unit is a field effect transistor or a bipolar junction transistor.

5. The battery protection circuit according to claim 1, characterized in that: The first detection module (30) is also preset with a first warning voltage, the first detection module (30) compares the voltage signal with the first warning voltage, and outputs a second control signal to the control end based on the comparison result, and the protection switch module conducts the first connection end and the second connection end based on the second control signal.

6. The battery protection circuit according to claim 1 or 5, characterized in that: The second detection module (40) is preset with a second warning voltage, the second detection module (40) compares the voltage signal with the second warning voltage, and based on the comparison result, cuts off the path between the second connection end of the second detection module (40) and the third connection end of the second detection module (40).

7. The battery protection circuit according to claim 1, characterized in that: The second voltage has a value greater than the first voltage.

8. The battery protection circuit according to claim 1, characterized in that: The first detection module (30) further comprises a third connection terminal, the third connection terminal of the first detection module (30) being connected to the positive electrode of the power supply and being used to monitor the voltage signal of the positive electrode of the power supply, the first detection module (30) also being preset with a third voltage, the first detection module (30) comparing the voltage signal of the positive electrode of the power supply with the third voltage, and outputting a third control signal to the control terminal based on the comparison result, and the protection switch module shuts off the path between the first connection terminal and the second connection terminal based on the third control signal.

9. The battery protection circuit according to claim 1, characterized in that: The first detection module (30) further comprises a voltage stabilizing unit, the voltage stabilizing unit comprises a voltage stabilizing resistor, and two ends of the voltage stabilizing resistor are respectively connected between the output end of the first detection module (30) and the node.

10. The battery protection circuit according to claim 3, characterized in that: The second detection module (40) further comprises a current limiting unit, the current limiting unit comprising a current limiting resistor, one end of the current limiting resistor being connected to the first end connected to the switch unit, and the other end of the current limiting resistor serving as the first connection end of the second detection module (40).

11. An electronic device, characterized in that: The electronic device comprises the battery protection circuit according to any one of claims 1 to 10.

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